diff options
author | herbelin <herbelin@85f007b7-540e-0410-9357-904b9bb8a0f7> | 2003-11-29 17:28:49 +0000 |
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committer | herbelin <herbelin@85f007b7-540e-0410-9357-904b9bb8a0f7> | 2003-11-29 17:28:49 +0000 |
commit | 9a6e3fe764dc2543dfa94de20fe5eec42d6be705 (patch) | |
tree | 77c0021911e3696a8c98e35a51840800db4be2a9 /theories/Reals/SeqSeries.v | |
parent | 9058fb97426307536f56c3e7447be2f70798e081 (diff) |
Remplacement des fichiers .v ancienne syntaxe de theories, contrib et states par les fichiers nouvelle syntaxe
git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@5027 85f007b7-540e-0410-9357-904b9bb8a0f7
Diffstat (limited to 'theories/Reals/SeqSeries.v')
-rw-r--r-- | theories/Reals/SeqSeries.v | 660 |
1 files changed, 385 insertions, 275 deletions
diff --git a/theories/Reals/SeqSeries.v b/theories/Reals/SeqSeries.v index 03963fc4d..ffac3df29 100644 --- a/theories/Reals/SeqSeries.v +++ b/theories/Reals/SeqSeries.v @@ -8,9 +8,9 @@ (*i $Id$ i*) -Require Rbase. -Require Rfunctions. -Require Max. +Require Import Rbase. +Require Import Rfunctions. +Require Import Max. Require Export Rseries. Require Export SeqProp. Require Export Rcomplete. @@ -21,287 +21,397 @@ Require Export Rsigma. Require Export Rprod. Require Export Cauchy_prod. Require Export Alembert. -V7only [ Import nat_scope. Import Z_scope. Import R_scope. ]. Open Local Scope R_scope. (**********) -Lemma sum_maj1 : (fn:nat->R->R;An:nat->R;x,l1,l2:R;N:nat) (Un_cv [n:nat](SP fn n x) l1) -> (Un_cv [n:nat](sum_f_R0 An n) l2) -> ((n:nat)``(Rabsolu (fn n x))<=(An n)``) -> ``(Rabsolu (l1-(SP fn N x)))<=l2-(sum_f_R0 An N)``. -Intros; Cut (sigTT R [l:R](Un_cv [n:nat](sum_f_R0 [l:nat](fn (plus (S N) l) x) n) l)). -Intro; Cut (sigTT R [l:R](Un_cv [n:nat](sum_f_R0 [l:nat](An (plus (S N) l)) n) l)). -Intro; Elim X; Intros l1N H2. -Elim X0; Intros l2N H3. -Cut ``l1-(SP fn N x)==l1N``. -Intro; Cut ``l2-(sum_f_R0 An N)==l2N``. -Intro; Rewrite H4; Rewrite H5. -Apply sum_cv_maj with [l:nat](An (plus (S N) l)) [l:nat][x:R](fn (plus (S N) l) x) x. -Unfold SP; Apply H2. -Apply H3. -Intros; Apply H1. -Symmetry; EApply UL_sequence. -Apply H3. -Unfold Un_cv in H0; Unfold Un_cv; Intros; Elim (H0 eps H5); Intros N0 H6. -Unfold R_dist in H6; Exists N0; Intros. -Unfold R_dist; Replace (Rminus (sum_f_R0 [l:nat](An (plus (S N) l)) n) (Rminus l2 (sum_f_R0 An N))) with (Rminus (Rplus (sum_f_R0 An N) (sum_f_R0 [l:nat](An (plus (S N) l)) n)) l2); [Idtac | Ring]. -Replace (Rplus (sum_f_R0 An N) (sum_f_R0 [l:nat](An (plus (S N) l)) n)) with (sum_f_R0 An (S (plus N n))). -Apply H6; Unfold ge; Apply le_trans with n. -Apply H7. -Apply le_trans with (plus N n). -Apply le_plus_r. -Apply le_n_Sn. -Cut (le O N). -Cut (lt N (S (plus N n))). -Intros; Assert H10 := (sigma_split An H9 H8). -Unfold sigma in H10. -Do 2 Rewrite <- minus_n_O in H10. -Replace (sum_f_R0 An (S (plus N n))) with (sum_f_R0 [k:nat](An (plus (0) k)) (S (plus N n))). -Replace (sum_f_R0 An N) with (sum_f_R0 [k:nat](An (plus (0) k)) N). -Cut (minus (S (plus N n)) (S N))=n. -Intro; Rewrite H11 in H10. -Apply H10. -Apply INR_eq; Rewrite minus_INR. -Do 2 Rewrite S_INR; Rewrite plus_INR; Ring. -Apply le_n_S; Apply le_plus_l. -Apply sum_eq; Intros. -Reflexivity. -Apply sum_eq; Intros. -Reflexivity. -Apply le_lt_n_Sm; Apply le_plus_l. -Apply le_O_n. -Symmetry; EApply UL_sequence. -Apply H2. -Unfold Un_cv in H; Unfold Un_cv; Intros. -Elim (H eps H4); Intros N0 H5. -Unfold R_dist in H5; Exists N0; Intros. -Unfold R_dist SP; Replace (Rminus (sum_f_R0 [l:nat](fn (plus (S N) l) x) n) (Rminus l1 (sum_f_R0 [k:nat](fn k x) N))) with (Rminus (Rplus (sum_f_R0 [k:nat](fn k x) N) (sum_f_R0 [l:nat](fn (plus (S N) l) x) n)) l1); [Idtac | Ring]. -Replace (Rplus (sum_f_R0 [k:nat](fn k x) N) (sum_f_R0 [l:nat](fn (plus (S N) l) x) n)) with (sum_f_R0 [k:nat](fn k x) (S (plus N n))). -Unfold SP in H5; Apply H5; Unfold ge; Apply le_trans with n. -Apply H6. -Apply le_trans with (plus N n). -Apply le_plus_r. -Apply le_n_Sn. -Cut (le O N). -Cut (lt N (S (plus N n))). -Intros; Assert H9 := (sigma_split [k:nat](fn k x) H8 H7). -Unfold sigma in H9. -Do 2 Rewrite <- minus_n_O in H9. -Replace (sum_f_R0 [k:nat](fn k x) (S (plus N n))) with (sum_f_R0 [k:nat](fn (plus (0) k) x) (S (plus N n))). -Replace (sum_f_R0 [k:nat](fn k x) N) with (sum_f_R0 [k:nat](fn (plus (0) k) x) N). -Cut (minus (S (plus N n)) (S N))=n. -Intro; Rewrite H10 in H9. -Apply H9. -Apply INR_eq; Rewrite minus_INR. -Do 2 Rewrite S_INR; Rewrite plus_INR; Ring. -Apply le_n_S; Apply le_plus_l. -Apply sum_eq; Intros. -Reflexivity. -Apply sum_eq; Intros. -Reflexivity. -Apply le_lt_n_Sm. -Apply le_plus_l. -Apply le_O_n. -Apply existTT with ``l2-(sum_f_R0 An N)``. -Unfold Un_cv in H0; Unfold Un_cv; Intros. -Elim (H0 eps H2); Intros N0 H3. -Unfold R_dist in H3; Exists N0; Intros. -Unfold R_dist; Replace (Rminus (sum_f_R0 [l:nat](An (plus (S N) l)) n) (Rminus l2 (sum_f_R0 An N))) with (Rminus (Rplus (sum_f_R0 An N) (sum_f_R0 [l:nat](An (plus (S N) l)) n)) l2); [Idtac | Ring]. -Replace (Rplus (sum_f_R0 An N) (sum_f_R0 [l:nat](An (plus (S N) l)) n)) with (sum_f_R0 An (S (plus N n))). -Apply H3; Unfold ge; Apply le_trans with n. -Apply H4. -Apply le_trans with (plus N n). -Apply le_plus_r. -Apply le_n_Sn. -Cut (le O N). -Cut (lt N (S (plus N n))). -Intros; Assert H7 := (sigma_split An H6 H5). -Unfold sigma in H7. -Do 2 Rewrite <- minus_n_O in H7. -Replace (sum_f_R0 An (S (plus N n))) with (sum_f_R0 [k:nat](An (plus (0) k)) (S (plus N n))). -Replace (sum_f_R0 An N) with (sum_f_R0 [k:nat](An (plus (0) k)) N). -Cut (minus (S (plus N n)) (S N))=n. -Intro; Rewrite H8 in H7. -Apply H7. -Apply INR_eq; Rewrite minus_INR. -Do 2 Rewrite S_INR; Rewrite plus_INR; Ring. -Apply le_n_S; Apply le_plus_l. -Apply sum_eq; Intros. -Reflexivity. -Apply sum_eq; Intros. -Reflexivity. -Apply le_lt_n_Sm. -Apply le_plus_l. -Apply le_O_n. -Apply existTT with ``l1-(SP fn N x)``. -Unfold Un_cv in H; Unfold Un_cv; Intros. -Elim (H eps H2); Intros N0 H3. -Unfold R_dist in H3; Exists N0; Intros. -Unfold R_dist SP. -Replace (Rminus (sum_f_R0 [l:nat](fn (plus (S N) l) x) n) (Rminus l1 (sum_f_R0 [k:nat](fn k x) N))) with (Rminus (Rplus (sum_f_R0 [k:nat](fn k x) N) (sum_f_R0 [l:nat](fn (plus (S N) l) x) n)) l1); [Idtac | Ring]. -Replace (Rplus (sum_f_R0 [k:nat](fn k x) N) (sum_f_R0 [l:nat](fn (plus (S N) l) x) n)) with (sum_f_R0 [k:nat](fn k x) (S (plus N n))). -Unfold SP in H3; Apply H3. -Unfold ge; Apply le_trans with n. -Apply H4. -Apply le_trans with (plus N n). -Apply le_plus_r. -Apply le_n_Sn. -Cut (le O N). -Cut (lt N (S (plus N n))). -Intros; Assert H7 := (sigma_split [k:nat](fn k x) H6 H5). -Unfold sigma in H7. -Do 2 Rewrite <- minus_n_O in H7. -Replace (sum_f_R0 [k:nat](fn k x) (S (plus N n))) with (sum_f_R0 [k:nat](fn (plus (0) k) x) (S (plus N n))). -Replace (sum_f_R0 [k:nat](fn k x) N) with (sum_f_R0 [k:nat](fn (plus (0) k) x) N). -Cut (minus (S (plus N n)) (S N))=n. -Intro; Rewrite H8 in H7. -Apply H7. -Apply INR_eq; Rewrite minus_INR. -Do 2 Rewrite S_INR; Rewrite plus_INR; Ring. -Apply le_n_S; Apply le_plus_l. -Apply sum_eq; Intros. -Reflexivity. -Apply sum_eq; Intros. -Reflexivity. -Apply le_lt_n_Sm. -Apply le_plus_l. -Apply le_O_n. +Lemma sum_maj1 : + forall (fn:nat -> R -> R) (An:nat -> R) (x l1 l2:R) + (N:nat), + Un_cv (fun n:nat => SP fn n x) l1 -> + Un_cv (fun n:nat => sum_f_R0 An n) l2 -> + (forall n:nat, Rabs (fn n x) <= An n) -> + Rabs (l1 - SP fn N x) <= l2 - sum_f_R0 An N. +intros; + cut + (sigT + (fun l:R => + Un_cv (fun n:nat => sum_f_R0 (fun l:nat => fn (S N + l)%nat x) n) l)). +intro; + cut + (sigT + (fun l:R => + Un_cv (fun n:nat => sum_f_R0 (fun l:nat => An (S N + l)%nat) n) l)). +intro; elim X; intros l1N H2. +elim X0; intros l2N H3. +cut (l1 - SP fn N x = l1N). +intro; cut (l2 - sum_f_R0 An N = l2N). +intro; rewrite H4; rewrite H5. +apply sum_cv_maj with + (fun l:nat => An (S N + l)%nat) (fun (l:nat) (x:R) => fn (S N + l)%nat x) x. +unfold SP in |- *; apply H2. +apply H3. +intros; apply H1. +symmetry in |- *; eapply UL_sequence. +apply H3. +unfold Un_cv in H0; unfold Un_cv in |- *; intros; elim (H0 eps H5); + intros N0 H6. +unfold R_dist in H6; exists N0; intros. +unfold R_dist in |- *; + replace (sum_f_R0 (fun l:nat => An (S N + l)%nat) n - (l2 - sum_f_R0 An N)) + with (sum_f_R0 An N + sum_f_R0 (fun l:nat => An (S N + l)%nat) n - l2); + [ idtac | ring ]. +replace (sum_f_R0 An N + sum_f_R0 (fun l:nat => An (S N + l)%nat) n) with + (sum_f_R0 An (S (N + n))). +apply H6; unfold ge in |- *; apply le_trans with n. +apply H7. +apply le_trans with (N + n)%nat. +apply le_plus_r. +apply le_n_Sn. +cut (0 <= N)%nat. +cut (N < S (N + n))%nat. +intros; assert (H10 := sigma_split An H9 H8). +unfold sigma in H10. +do 2 rewrite <- minus_n_O in H10. +replace (sum_f_R0 An (S (N + n))) with + (sum_f_R0 (fun k:nat => An (0 + k)%nat) (S (N + n))). +replace (sum_f_R0 An N) with (sum_f_R0 (fun k:nat => An (0 + k)%nat) N). +cut ((S (N + n) - S N)%nat = n). +intro; rewrite H11 in H10. +apply H10. +apply INR_eq; rewrite minus_INR. +do 2 rewrite S_INR; rewrite plus_INR; ring. +apply le_n_S; apply le_plus_l. +apply sum_eq; intros. +reflexivity. +apply sum_eq; intros. +reflexivity. +apply le_lt_n_Sm; apply le_plus_l. +apply le_O_n. +symmetry in |- *; eapply UL_sequence. +apply H2. +unfold Un_cv in H; unfold Un_cv in |- *; intros. +elim (H eps H4); intros N0 H5. +unfold R_dist in H5; exists N0; intros. +unfold R_dist, SP in |- *; + replace + (sum_f_R0 (fun l:nat => fn (S N + l)%nat x) n - + (l1 - sum_f_R0 (fun k:nat => fn k x) N)) with + (sum_f_R0 (fun k:nat => fn k x) N + + sum_f_R0 (fun l:nat => fn (S N + l)%nat x) n - l1); + [ idtac | ring ]. +replace + (sum_f_R0 (fun k:nat => fn k x) N + + sum_f_R0 (fun l:nat => fn (S N + l)%nat x) n) with + (sum_f_R0 (fun k:nat => fn k x) (S (N + n))). +unfold SP in H5; apply H5; unfold ge in |- *; apply le_trans with n. +apply H6. +apply le_trans with (N + n)%nat. +apply le_plus_r. +apply le_n_Sn. +cut (0 <= N)%nat. +cut (N < S (N + n))%nat. +intros; assert (H9 := sigma_split (fun k:nat => fn k x) H8 H7). +unfold sigma in H9. +do 2 rewrite <- minus_n_O in H9. +replace (sum_f_R0 (fun k:nat => fn k x) (S (N + n))) with + (sum_f_R0 (fun k:nat => fn (0 + k)%nat x) (S (N + n))). +replace (sum_f_R0 (fun k:nat => fn k x) N) with + (sum_f_R0 (fun k:nat => fn (0 + k)%nat x) N). +cut ((S (N + n) - S N)%nat = n). +intro; rewrite H10 in H9. +apply H9. +apply INR_eq; rewrite minus_INR. +do 2 rewrite S_INR; rewrite plus_INR; ring. +apply le_n_S; apply le_plus_l. +apply sum_eq; intros. +reflexivity. +apply sum_eq; intros. +reflexivity. +apply le_lt_n_Sm. +apply le_plus_l. +apply le_O_n. +apply existT with (l2 - sum_f_R0 An N). +unfold Un_cv in H0; unfold Un_cv in |- *; intros. +elim (H0 eps H2); intros N0 H3. +unfold R_dist in H3; exists N0; intros. +unfold R_dist in |- *; + replace (sum_f_R0 (fun l:nat => An (S N + l)%nat) n - (l2 - sum_f_R0 An N)) + with (sum_f_R0 An N + sum_f_R0 (fun l:nat => An (S N + l)%nat) n - l2); + [ idtac | ring ]. +replace (sum_f_R0 An N + sum_f_R0 (fun l:nat => An (S N + l)%nat) n) with + (sum_f_R0 An (S (N + n))). +apply H3; unfold ge in |- *; apply le_trans with n. +apply H4. +apply le_trans with (N + n)%nat. +apply le_plus_r. +apply le_n_Sn. +cut (0 <= N)%nat. +cut (N < S (N + n))%nat. +intros; assert (H7 := sigma_split An H6 H5). +unfold sigma in H7. +do 2 rewrite <- minus_n_O in H7. +replace (sum_f_R0 An (S (N + n))) with + (sum_f_R0 (fun k:nat => An (0 + k)%nat) (S (N + n))). +replace (sum_f_R0 An N) with (sum_f_R0 (fun k:nat => An (0 + k)%nat) N). +cut ((S (N + n) - S N)%nat = n). +intro; rewrite H8 in H7. +apply H7. +apply INR_eq; rewrite minus_INR. +do 2 rewrite S_INR; rewrite plus_INR; ring. +apply le_n_S; apply le_plus_l. +apply sum_eq; intros. +reflexivity. +apply sum_eq; intros. +reflexivity. +apply le_lt_n_Sm. +apply le_plus_l. +apply le_O_n. +apply existT with (l1 - SP fn N x). +unfold Un_cv in H; unfold Un_cv in |- *; intros. +elim (H eps H2); intros N0 H3. +unfold R_dist in H3; exists N0; intros. +unfold R_dist, SP in |- *. +replace + (sum_f_R0 (fun l:nat => fn (S N + l)%nat x) n - + (l1 - sum_f_R0 (fun k:nat => fn k x) N)) with + (sum_f_R0 (fun k:nat => fn k x) N + + sum_f_R0 (fun l:nat => fn (S N + l)%nat x) n - l1); + [ idtac | ring ]. +replace + (sum_f_R0 (fun k:nat => fn k x) N + + sum_f_R0 (fun l:nat => fn (S N + l)%nat x) n) with + (sum_f_R0 (fun k:nat => fn k x) (S (N + n))). +unfold SP in H3; apply H3. +unfold ge in |- *; apply le_trans with n. +apply H4. +apply le_trans with (N + n)%nat. +apply le_plus_r. +apply le_n_Sn. +cut (0 <= N)%nat. +cut (N < S (N + n))%nat. +intros; assert (H7 := sigma_split (fun k:nat => fn k x) H6 H5). +unfold sigma in H7. +do 2 rewrite <- minus_n_O in H7. +replace (sum_f_R0 (fun k:nat => fn k x) (S (N + n))) with + (sum_f_R0 (fun k:nat => fn (0 + k)%nat x) (S (N + n))). +replace (sum_f_R0 (fun k:nat => fn k x) N) with + (sum_f_R0 (fun k:nat => fn (0 + k)%nat x) N). +cut ((S (N + n) - S N)%nat = n). +intro; rewrite H8 in H7. +apply H7. +apply INR_eq; rewrite minus_INR. +do 2 rewrite S_INR; rewrite plus_INR; ring. +apply le_n_S; apply le_plus_l. +apply sum_eq; intros. +reflexivity. +apply sum_eq; intros. +reflexivity. +apply le_lt_n_Sm. +apply le_plus_l. +apply le_O_n. Qed. (* Comparaison of convergence for series *) -Lemma Rseries_CV_comp : (An,Bn:nat->R) ((n:nat)``0<=(An n)<=(Bn n)``) -> (sigTT ? [l:R](Un_cv [N:nat](sum_f_R0 Bn N) l)) -> (sigTT ? [l:R](Un_cv [N:nat](sum_f_R0 An N) l)). -Intros; Apply cv_cauchy_2. -Assert H0 := (cv_cauchy_1 ? X). -Unfold Cauchy_crit_series; Unfold Cauchy_crit. -Intros; Elim (H0 eps H1); Intros. -Exists x; Intros. -Cut (Rle (R_dist (sum_f_R0 An n) (sum_f_R0 An m)) (R_dist (sum_f_R0 Bn n) (sum_f_R0 Bn m))). -Intro; Apply Rle_lt_trans with (R_dist (sum_f_R0 Bn n) (sum_f_R0 Bn m)). -Assumption. -Apply H2; Assumption. -Assert H5 := (lt_eq_lt_dec n m). -Elim H5; Intro. -Elim a; Intro. -Rewrite (tech2 An n m); [Idtac | Assumption]. -Rewrite (tech2 Bn n m); [Idtac | Assumption]. -Unfold R_dist; Unfold Rminus; Do 2 Rewrite Ropp_distr1; Do 2 Rewrite <- Rplus_assoc; Do 2 Rewrite Rplus_Ropp_r; Do 2 Rewrite Rplus_Ol; Do 2 Rewrite Rabsolu_Ropp; Repeat Rewrite Rabsolu_right. -Apply sum_Rle; Intros. -Elim (H (plus (S n) n0)); Intros. -Apply H8. -Apply Rle_sym1; Apply cond_pos_sum; Intro. -Elim (H (plus (S n) n0)); Intros. -Apply Rle_trans with (An (plus (S n) n0)); Assumption. -Apply Rle_sym1; Apply cond_pos_sum; Intro. -Elim (H (plus (S n) n0)); Intros; Assumption. -Rewrite b; Unfold R_dist; Unfold Rminus; Do 2 Rewrite Rplus_Ropp_r; Rewrite Rabsolu_R0; Right; Reflexivity. -Rewrite (tech2 An m n); [Idtac | Assumption]. -Rewrite (tech2 Bn m n); [Idtac | Assumption]. -Unfold R_dist; Unfold Rminus; Do 2 Rewrite Rplus_assoc; Rewrite (Rplus_sym (sum_f_R0 An m)); Rewrite (Rplus_sym (sum_f_R0 Bn m)); Do 2 Rewrite Rplus_assoc; Do 2 Rewrite Rplus_Ropp_l; Do 2 Rewrite Rplus_Or; Repeat Rewrite Rabsolu_right. -Apply sum_Rle; Intros. -Elim (H (plus (S m) n0)); Intros; Apply H8. -Apply Rle_sym1; Apply cond_pos_sum; Intro. -Elim (H (plus (S m) n0)); Intros. -Apply Rle_trans with (An (plus (S m) n0)); Assumption. -Apply Rle_sym1. -Apply cond_pos_sum; Intro. -Elim (H (plus (S m) n0)); Intros; Assumption. +Lemma Rseries_CV_comp : + forall An Bn:nat -> R, + (forall n:nat, 0 <= An n <= Bn n) -> + sigT (fun l:R => Un_cv (fun N:nat => sum_f_R0 Bn N) l) -> + sigT (fun l:R => Un_cv (fun N:nat => sum_f_R0 An N) l). +intros; apply cv_cauchy_2. +assert (H0 := cv_cauchy_1 _ X). +unfold Cauchy_crit_series in |- *; unfold Cauchy_crit in |- *. +intros; elim (H0 eps H1); intros. +exists x; intros. +cut + (R_dist (sum_f_R0 An n) (sum_f_R0 An m) <= + R_dist (sum_f_R0 Bn n) (sum_f_R0 Bn m)). +intro; apply Rle_lt_trans with (R_dist (sum_f_R0 Bn n) (sum_f_R0 Bn m)). +assumption. +apply H2; assumption. +assert (H5 := lt_eq_lt_dec n m). +elim H5; intro. +elim a; intro. +rewrite (tech2 An n m); [ idtac | assumption ]. +rewrite (tech2 Bn n m); [ idtac | assumption ]. +unfold R_dist in |- *; unfold Rminus in |- *; do 2 rewrite Ropp_plus_distr; + do 2 rewrite <- Rplus_assoc; do 2 rewrite Rplus_opp_r; + do 2 rewrite Rplus_0_l; do 2 rewrite Rabs_Ropp; repeat rewrite Rabs_right. +apply sum_Rle; intros. +elim (H (S n + n0)%nat); intros. +apply H8. +apply Rle_ge; apply cond_pos_sum; intro. +elim (H (S n + n0)%nat); intros. +apply Rle_trans with (An (S n + n0)%nat); assumption. +apply Rle_ge; apply cond_pos_sum; intro. +elim (H (S n + n0)%nat); intros; assumption. +rewrite b; unfold R_dist in |- *; unfold Rminus in |- *; + do 2 rewrite Rplus_opp_r; rewrite Rabs_R0; right; + reflexivity. +rewrite (tech2 An m n); [ idtac | assumption ]. +rewrite (tech2 Bn m n); [ idtac | assumption ]. +unfold R_dist in |- *; unfold Rminus in |- *; do 2 rewrite Rplus_assoc; + rewrite (Rplus_comm (sum_f_R0 An m)); rewrite (Rplus_comm (sum_f_R0 Bn m)); + do 2 rewrite Rplus_assoc; do 2 rewrite Rplus_opp_l; + do 2 rewrite Rplus_0_r; repeat rewrite Rabs_right. +apply sum_Rle; intros. +elim (H (S m + n0)%nat); intros; apply H8. +apply Rle_ge; apply cond_pos_sum; intro. +elim (H (S m + n0)%nat); intros. +apply Rle_trans with (An (S m + n0)%nat); assumption. +apply Rle_ge. +apply cond_pos_sum; intro. +elim (H (S m + n0)%nat); intros; assumption. Qed. (* Cesaro's theorem *) -Lemma Cesaro : (An,Bn:nat->R;l:R) (Un_cv Bn l) -> ((n:nat)``0<(An n)``) -> (cv_infty [n:nat](sum_f_R0 An n)) -> (Un_cv [n:nat](Rdiv (sum_f_R0 [k:nat]``(An k)*(Bn k)`` n) (sum_f_R0 An n)) l). -Proof with Trivial. -Unfold Un_cv; Intros; Assert H3 : (n:nat)``0<(sum_f_R0 An n)``. -Intro; Apply tech1. -Assert H4 : (n:nat) ``(sum_f_R0 An n)<>0``. -Intro; Red; Intro; Assert H5 := (H3 n); Rewrite H4 in H5; Elim (Rlt_antirefl ? H5). -Assert H5 := (cv_infty_cv_R0 ? H4 H1); Assert H6 : ``0<eps/2``. -Unfold Rdiv; Apply Rmult_lt_pos. -Apply Rlt_Rinv; Sup. -Elim (H ? H6); Clear H; Intros N1 H; Pose C := (Rabsolu (sum_f_R0 [k:nat]``(An k)*((Bn k)-l)`` N1)); Assert H7 : (EX N:nat | (n:nat) (le N n) -> ``C/(sum_f_R0 An n)<eps/2``). -Case (Req_EM C R0); Intro. -Exists O; Intros. -Rewrite H7; Unfold Rdiv; Rewrite Rmult_Ol; Apply Rmult_lt_pos. -Apply Rlt_Rinv; Sup. -Assert H8 : ``0<eps/(2*(Rabsolu C))``. -Unfold Rdiv; Apply Rmult_lt_pos. -Apply Rlt_Rinv; Apply Rmult_lt_pos. -Sup. -Apply Rabsolu_pos_lt. -Elim (H5 ? H8); Intros; Exists x; Intros; Assert H11 := (H9 ? H10); Unfold R_dist in H11; Unfold Rminus in H11; Rewrite Ropp_O in H11; Rewrite Rplus_Or in H11. -Apply Rle_lt_trans with (Rabsolu ``C/(sum_f_R0 An n)``). -Apply Rle_Rabsolu. -Unfold Rdiv; Rewrite Rabsolu_mult; Apply Rlt_monotony_contra with ``/(Rabsolu C)``. -Apply Rlt_Rinv; Apply Rabsolu_pos_lt. -Rewrite <- Rmult_assoc; Rewrite <- Rinv_l_sym. -Rewrite Rmult_1l; Replace ``/(Rabsolu C)*(eps*/2)`` with ``eps/(2*(Rabsolu C))``. -Unfold Rdiv; Rewrite Rinv_Rmult. -Ring. -DiscrR. -Apply Rabsolu_no_R0. -Apply Rabsolu_no_R0. -Elim H7; Clear H7; Intros N2 H7; Pose N := (max N1 N2); Exists (S N); Intros; Unfold R_dist; Replace (Rminus (Rdiv (sum_f_R0 [k:nat]``(An k)*(Bn k)`` n) (sum_f_R0 An n)) l) with (Rdiv (sum_f_R0 [k:nat]``(An k)*((Bn k)-l)`` n) (sum_f_R0 An n)). -Assert H9 : (lt N1 n). -Apply lt_le_trans with (S N). -Apply le_lt_n_Sm; Unfold N; Apply le_max_l. -Rewrite (tech2 [k:nat]``(An k)*((Bn k)-l)`` ? ? H9); Unfold Rdiv; Rewrite Rmult_Rplus_distrl; Apply Rle_lt_trans with (Rplus (Rabsolu (Rdiv (sum_f_R0 [k:nat]``(An k)*((Bn k)-l)`` N1) (sum_f_R0 An n))) (Rabsolu (Rdiv (sum_f_R0 [i:nat]``(An (plus (S N1) i))*((Bn (plus (S N1) i))-l)`` (minus n (S N1))) (sum_f_R0 An n)))). -Apply Rabsolu_triang. -Rewrite (double_var eps); Apply Rplus_lt. -Unfold Rdiv; Rewrite Rabsolu_mult; Fold C; Rewrite Rabsolu_right. -Apply (H7 n); Apply le_trans with (S N). -Apply le_trans with N; [Unfold N; Apply le_max_r | Apply le_n_Sn]. -Apply Rle_sym1; Left; Apply Rlt_Rinv. +Lemma Cesaro : + forall (An Bn:nat -> R) (l:R), + Un_cv Bn l -> + (forall n:nat, 0 < An n) -> + cv_infty (fun n:nat => sum_f_R0 An n) -> + Un_cv (fun n:nat => sum_f_R0 (fun k:nat => An k * Bn k) n / sum_f_R0 An n) + l. +Proof with trivial. +unfold Un_cv in |- *; intros; assert (H3 : forall n:nat, 0 < sum_f_R0 An n)... +intro; apply tech1... +assert (H4 : forall n:nat, sum_f_R0 An n <> 0)... +intro; red in |- *; intro; assert (H5 := H3 n); rewrite H4 in H5; + elim (Rlt_irrefl _ H5)... +assert (H5 := cv_infty_cv_R0 _ H4 H1); assert (H6 : 0 < eps / 2)... +unfold Rdiv in |- *; apply Rmult_lt_0_compat... +apply Rinv_0_lt_compat; prove_sup... +elim (H _ H6); clear H; intros N1 H; + pose (C := Rabs (sum_f_R0 (fun k:nat => An k * (Bn k - l)) N1)); + assert + (H7 : + exists N : nat + | (forall n:nat, (N <= n)%nat -> C / sum_f_R0 An n < eps / 2))... +case (Req_dec C 0); intro... +exists 0%nat; intros... +rewrite H7; unfold Rdiv in |- *; rewrite Rmult_0_l; apply Rmult_lt_0_compat... +apply Rinv_0_lt_compat; prove_sup... +assert (H8 : 0 < eps / (2 * Rabs C))... +unfold Rdiv in |- *; apply Rmult_lt_0_compat... +apply Rinv_0_lt_compat; apply Rmult_lt_0_compat... +prove_sup... +apply Rabs_pos_lt... +elim (H5 _ H8); intros; exists x; intros; assert (H11 := H9 _ H10); + unfold R_dist in H11; unfold Rminus in H11; rewrite Ropp_0 in H11; + rewrite Rplus_0_r in H11... +apply Rle_lt_trans with (Rabs (C / sum_f_R0 An n))... +apply RRle_abs... +unfold Rdiv in |- *; rewrite Rabs_mult; apply Rmult_lt_reg_l with (/ Rabs C)... +apply Rinv_0_lt_compat; apply Rabs_pos_lt... +rewrite <- Rmult_assoc; rewrite <- Rinv_l_sym... +rewrite Rmult_1_l; replace (/ Rabs C * (eps * / 2)) with (eps / (2 * Rabs C))... +unfold Rdiv in |- *; rewrite Rinv_mult_distr... +ring... +discrR... +apply Rabs_no_R0... +apply Rabs_no_R0... +elim H7; clear H7; intros N2 H7; pose (N := max N1 N2); exists (S N); intros; + unfold R_dist in |- *; + replace (sum_f_R0 (fun k:nat => An k * Bn k) n / sum_f_R0 An n - l) with + (sum_f_R0 (fun k:nat => An k * (Bn k - l)) n / sum_f_R0 An n)... +assert (H9 : (N1 < n)%nat)... +apply lt_le_trans with (S N)... +apply le_lt_n_Sm; unfold N in |- *; apply le_max_l... +rewrite (tech2 (fun k:nat => An k * (Bn k - l)) _ _ H9); unfold Rdiv in |- *; + rewrite Rmult_plus_distr_r; + apply Rle_lt_trans with + (Rabs (sum_f_R0 (fun k:nat => An k * (Bn k - l)) N1 / sum_f_R0 An n) + + Rabs + (sum_f_R0 (fun i:nat => An (S N1 + i)%nat * (Bn (S N1 + i)%nat - l)) + (n - S N1) / sum_f_R0 An n))... +apply Rabs_triang... +rewrite (double_var eps); apply Rplus_lt_compat... +unfold Rdiv in |- *; rewrite Rabs_mult; fold C in |- *; rewrite Rabs_right... +apply (H7 n); apply le_trans with (S N)... +apply le_trans with N; [ unfold N in |- *; apply le_max_r | apply le_n_Sn ]... +apply Rle_ge; left; apply Rinv_0_lt_compat... -Unfold R_dist in H; Unfold Rdiv; Rewrite Rabsolu_mult; Rewrite (Rabsolu_right ``/(sum_f_R0 An n)``). -Apply Rle_lt_trans with (Rmult (sum_f_R0 [i:nat](Rabsolu ``(An (plus (S N1) i))*((Bn (plus (S N1) i))-l)``) (minus n (S N1))) ``/(sum_f_R0 An n)``). -Do 2 Rewrite <- (Rmult_sym ``/(sum_f_R0 An n)``); Apply Rle_monotony. -Left; Apply Rlt_Rinv. -Apply (sum_Rabsolu [i:nat]``(An (plus (S N1) i))*((Bn (plus (S N1) i))-l)`` (minus n (S N1))). -Apply Rle_lt_trans with (Rmult (sum_f_R0 [i:nat]``(An (plus (S N1) i))*eps/2`` (minus n (S N1))) ``/(sum_f_R0 An n)``). -Do 2 Rewrite <- (Rmult_sym ``/(sum_f_R0 An n)``); Apply Rle_monotony. -Left; Apply Rlt_Rinv. -Apply sum_Rle; Intros; Rewrite Rabsolu_mult; Pattern 2 (An (plus (S N1) n0)); Rewrite <- (Rabsolu_right (An (plus (S N1) n0))). -Apply Rle_monotony. -Apply Rabsolu_pos. -Left; Apply H; Unfold ge; Apply le_trans with (S N1); [Apply le_n_Sn | Apply le_plus_l]. -Apply Rle_sym1; Left. -Rewrite <- (scal_sum [i:nat](An (plus (S N1) i)) (minus n (S N1)) ``eps/2``); Unfold Rdiv; Repeat Rewrite Rmult_assoc; Apply Rlt_monotony. -Pattern 2 ``/2``; Rewrite <- Rmult_1r; Apply Rlt_monotony. -Apply Rlt_Rinv; Sup. -Rewrite Rmult_sym; Apply Rlt_monotony_contra with (sum_f_R0 An n). -Rewrite <- Rmult_assoc; Rewrite <- Rinv_r_sym. -Rewrite Rmult_1l; Rewrite Rmult_1r; Rewrite (tech2 An N1 n). -Rewrite Rplus_sym; Pattern 1 (sum_f_R0 [i:nat](An (plus (S N1) i)) (minus n (S N1))); Rewrite <- Rplus_Or; Apply Rlt_compatibility. -Apply Rle_sym1; Left; Apply Rlt_Rinv. -Replace (sum_f_R0 [k:nat]``(An k)*((Bn k)-l)`` n) with (Rplus (sum_f_R0 [k:nat]``(An k)*(Bn k)`` n) (sum_f_R0 [k:nat]``(An k)*-l`` n)). -Rewrite <- (scal_sum An n ``-l``); Field. -Rewrite <- plus_sum; Apply sum_eq; Intros; Ring. +unfold R_dist in H; unfold Rdiv in |- *; rewrite Rabs_mult; + rewrite (Rabs_right (/ sum_f_R0 An n))... +apply Rle_lt_trans with + (sum_f_R0 (fun i:nat => Rabs (An (S N1 + i)%nat * (Bn (S N1 + i)%nat - l))) + (n - S N1) * / sum_f_R0 An n)... +do 2 rewrite <- (Rmult_comm (/ sum_f_R0 An n)); apply Rmult_le_compat_l... +left; apply Rinv_0_lt_compat... +apply + (Rsum_abs (fun i:nat => An (S N1 + i)%nat * (Bn (S N1 + i)%nat - l)) + (n - S N1))... +apply Rle_lt_trans with + (sum_f_R0 (fun i:nat => An (S N1 + i)%nat * (eps / 2)) (n - S N1) * + / sum_f_R0 An n)... +do 2 rewrite <- (Rmult_comm (/ sum_f_R0 An n)); apply Rmult_le_compat_l... +left; apply Rinv_0_lt_compat... +apply sum_Rle; intros; rewrite Rabs_mult; + pattern (An (S N1 + n0)%nat) at 2 in |- *; + rewrite <- (Rabs_right (An (S N1 + n0)%nat))... +apply Rmult_le_compat_l... +apply Rabs_pos... +left; apply H; unfold ge in |- *; apply le_trans with (S N1); + [ apply le_n_Sn | apply le_plus_l ]... +apply Rle_ge; left... +rewrite <- (scal_sum (fun i:nat => An (S N1 + i)%nat) (n - S N1) (eps / 2)); + unfold Rdiv in |- *; repeat rewrite Rmult_assoc; apply Rmult_lt_compat_l... +pattern (/ 2) at 2 in |- *; rewrite <- Rmult_1_r; apply Rmult_lt_compat_l... +apply Rinv_0_lt_compat; prove_sup... +rewrite Rmult_comm; apply Rmult_lt_reg_l with (sum_f_R0 An n)... +rewrite <- Rmult_assoc; rewrite <- Rinv_r_sym... +rewrite Rmult_1_l; rewrite Rmult_1_r; rewrite (tech2 An N1 n)... +rewrite Rplus_comm; + pattern (sum_f_R0 (fun i:nat => An (S N1 + i)%nat) (n - S N1)) at 1 in |- *; + rewrite <- Rplus_0_r; apply Rplus_lt_compat_l... +apply Rle_ge; left; apply Rinv_0_lt_compat... +replace (sum_f_R0 (fun k:nat => An k * (Bn k - l)) n) with + (sum_f_R0 (fun k:nat => An k * Bn k) n + + sum_f_R0 (fun k:nat => An k * - l) n)... +rewrite <- (scal_sum An n (- l)); field... +rewrite <- plus_sum; apply sum_eq; intros; ring... Qed. -Lemma Cesaro_1 : (An:nat->R;l:R) (Un_cv An l) -> (Un_cv [n:nat]``(sum_f_R0 An (pred n))/(INR n)`` l). -Proof with Trivial. -Intros Bn l H; Pose An := [_:nat]R1. -Assert H0 : (n:nat) ``0<(An n)``. -Intro; Unfold An; Apply Rlt_R0_R1. -Assert H1 : (n:nat)``0<(sum_f_R0 An n)``. -Intro; Apply tech1. -Assert H2 : (cv_infty [n:nat](sum_f_R0 An n)). -Unfold cv_infty; Intro; Case (total_order_Rle M R0); Intro. -Exists O; Intros; Apply Rle_lt_trans with R0. -Assert H2 : ``0<M``. -Auto with real. -Clear n; Pose m := (up M); Elim (archimed M); Intros; Assert H5 : `0<=m`. -Apply le_IZR; Unfold m; Simpl; Left; Apply Rlt_trans with M. -Elim (IZN ? H5); Intros; Exists x; Intros; Unfold An; Rewrite sum_cte; Rewrite Rmult_1l; Apply Rlt_trans with (IZR (up M)). -Apply Rle_lt_trans with (INR x). -Rewrite INR_IZR_INZ; Fold m; Rewrite <- H6; Right. -Apply lt_INR; Apply le_lt_n_Sm. -Assert H3 := (Cesaro ? ? ? H H0 H2). -Unfold Un_cv; Unfold Un_cv in H3; Intros; Elim (H3 ? H4); Intros; Exists (S x); Intros; Unfold R_dist; Unfold R_dist in H5; Apply Rle_lt_trans with (Rabsolu (Rminus (Rdiv (sum_f_R0 [k:nat]``(An k)*(Bn k)`` (pred n)) (sum_f_R0 An (pred n))) l)). -Right; Replace ``(sum_f_R0 Bn (pred n))/(INR n)-l`` with (Rminus (Rdiv (sum_f_R0 [k:nat]``(An k)*(Bn k)`` (pred n)) (sum_f_R0 An (pred n))) l). -Unfold Rminus; Do 2 Rewrite <- (Rplus_sym ``-l``); Apply Rplus_plus_r. -Unfold An; Replace (sum_f_R0 [k:nat]``1*(Bn k)`` (pred n)) with (sum_f_R0 Bn (pred n)). -Rewrite sum_cte; Rewrite Rmult_1l; Replace (S (pred n)) with n. -Apply S_pred with O; Apply lt_le_trans with (S x). -Apply lt_O_Sn. -Apply sum_eq; Intros; Ring. -Apply H5; Unfold ge; Apply le_S_n; Replace (S (pred n)) with n. -Apply S_pred with O; Apply lt_le_trans with (S x). -Apply lt_O_Sn. -Qed. +Lemma Cesaro_1 : + forall (An:nat -> R) (l:R), + Un_cv An l -> Un_cv (fun n:nat => sum_f_R0 An (pred n) / INR n) l. +Proof with trivial. +intros Bn l H; pose (An := fun _:nat => 1)... +assert (H0 : forall n:nat, 0 < An n)... +intro; unfold An in |- *; apply Rlt_0_1... +assert (H1 : forall n:nat, 0 < sum_f_R0 An n)... +intro; apply tech1... +assert (H2 : cv_infty (fun n:nat => sum_f_R0 An n))... +unfold cv_infty in |- *; intro; case (Rle_dec M 0); intro... +exists 0%nat; intros; apply Rle_lt_trans with 0... +assert (H2 : 0 < M)... +auto with real... +clear n; pose (m := up M); elim (archimed M); intros; + assert (H5 : (0 <= m)%Z)... +apply le_IZR; unfold m in |- *; simpl in |- *; left; apply Rlt_trans with M... +elim (IZN _ H5); intros; exists x; intros; unfold An in |- *; rewrite sum_cte; + rewrite Rmult_1_l; apply Rlt_trans with (IZR (up M))... +apply Rle_lt_trans with (INR x)... +rewrite INR_IZR_INZ; fold m in |- *; rewrite <- H6; right... +apply lt_INR; apply le_lt_n_Sm... +assert (H3 := Cesaro _ _ _ H H0 H2)... +unfold Un_cv in |- *; unfold Un_cv in H3; intros; elim (H3 _ H4); intros; + exists (S x); intros; unfold R_dist in |- *; unfold R_dist in H5; + apply Rle_lt_trans with + (Rabs + (sum_f_R0 (fun k:nat => An k * Bn k) (pred n) / sum_f_R0 An (pred n) - l))... +right; + replace (sum_f_R0 Bn (pred n) / INR n - l) with + (sum_f_R0 (fun k:nat => An k * Bn k) (pred n) / sum_f_R0 An (pred n) - l)... +unfold Rminus in |- *; do 2 rewrite <- (Rplus_comm (- l)); + apply Rplus_eq_compat_l... +unfold An in |- *; + replace (sum_f_R0 (fun k:nat => 1 * Bn k) (pred n)) with + (sum_f_R0 Bn (pred n))... +rewrite sum_cte; rewrite Rmult_1_l; replace (S (pred n)) with n... +apply S_pred with 0%nat; apply lt_le_trans with (S x)... +apply lt_O_Sn... +apply sum_eq; intros; ring... +apply H5; unfold ge in |- *; apply le_S_n; replace (S (pred n)) with n... +apply S_pred with 0%nat; apply lt_le_trans with (S x)... +apply lt_O_Sn... +Qed.
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